Effects of Nitrogen Application Rate on Yield Formation and Nitrogen Use Efficiency of Spring Maize

Xiangnongyu No.14 was used as material to study the effects of nitrogen application rate on yield formation and nitrogen use efficiency (NUE) of spring maize in Chenzhou,Hunan province,and the main results showed that along with increase of nitrogen application rate from 0 to 270 kg/hm2,plant height and leaf number of Xiangnongyu No.14 were increased,ear characteristics were improved evidently,volume of sink was increased significantly,duration of filling stage was prolonged 2～3 d,and the yield was increased significantly,while the yield difference between 180 kg/hm2 and 270 kg/hm2 treatment was not significant.NUE of Xiangnongyu No.14 was decreased significantly along with increase of nitrogen application rate.These results showed that about 180 kg/hm2 was appropriate to Xiangnongyu No.14 under conditions in this study,which could result in higher yield and NUE.